Keystone Species Dynamics

Keystone species have impacts far exceeding their biomass because they regulate interactions between other species. Sea otters in kelp forest ecosystems exemplify this: as predators of sea urchins, they prevent urchin population explosions that would devastate kelp forests and eliminate habitat for dozens of other species. Removing the keystone species causes cascading effects through the ecosystem. The modular trophic structure (producer-herbivore-carnivore) doesn't capture this keystone dynamic, which involves system-level properties emerging from specific network configurations.